Hello, everyone!
I am using Porteus Kiosk with white-list option. But every new tab opens with image "Access denied".
I want to make this page more user-friendly and change it to homepage or some other page.
But after unpacking squashfs images i didn't find image or html files.
How can I customize the default page? Or set redirect to homepage.

In the Location bar, type about:config and press Enter.
The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise! to continue to the about:config page.
Type browser.newtab.url in the search box.
Double-click the browser.newtab.url preference and change the url from about:newtab to about:blank. Alternately, you can change it to about:home for the Firefox Google home page, or type in your preferred home page, for example google.com.
Click OK and close the about:config tab.

In the Location bar, type about:config and press Enter.
The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise! to continue to the about:config page.
Type browser.newtab.url in the search box.
Double-click the browser.newtab.url preference and change the url from about:newtab to about:blank. Alternately, you can change it to about:home for the Firefox Google home page, or type in your preferred home page, for example google.com.
Click OK and close the about:config tab.

@Moakes : It's the PKE edition, since it is secured by concept, you can't access to the firefox/iceweasle... configuration. (tested myself by adding about:config on white-list and did not work).

If you give a man a fish, he eats for a day. Teach him how to fish and he will eat forever...

Debadr wrote:
@Moakes : It's the PKE edition, since it is secured by concept, you can't access to the firefox/iceweasle... configuration. (tested myself by adding about:config on white-list and did not work).

Sorry I left out a couple steps:
Extract the settings xzm as fatham mentioned.
Navigate to /003-settings/home/guest/.mozilla/firefox/c3pp43bg.default/
Edit prefs.js with Kwrite
Add the line: user_pref("browser.newtab.url", "youraddresshere.com");
Repack the module.
Remake the iso